//
// Created by nilyang on 2021/10/31.
//

#include "sockets.h"
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <unistd.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <string>

void func_sockets(int argc, char *argv[])
{
    int serv_sock;
    int clnt_sock;

    struct sockaddr_in serv_addr{};
    struct sockaddr_in clnt_addr{};
    socklen_t clnt_addr_size;

    char message[] = "Hello World!";

    if(argc!=2) {
        printf("Usage: %s <port>\n", argv[0]);
        exit(1);
    }

    serv_sock = socket(PF_INET, SOCK_STREAM, 0);
    if (serv_sock == -1) {
        show_error("socket() error");
    }

    memset(&serv_addr, 0, sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    serv_addr.sin_addr.s_addr = htonl(INADDR_ANY);
    serv_addr.sin_port = htons(atoi(argv[1]));

    if (bind(serv_sock, (struct sockaddr*)&serv_addr, sizeof(serv_addr))==-1)
    {
        show_error("bind() error");
    }

    if (listen(serv_sock, 5) == -1){
        show_error("listen() error");
    }

    clnt_addr_size = sizeof(clnt_addr);
    clnt_sock = accept(serv_sock, (struct sockaddr*)&clnt_addr,&clnt_addr_size);
    if (clnt_sock==-1){
        const char * err = "accept() error";
        show_error(err);
    }

    write(clnt_sock, message, sizeof(message));
    close(clnt_sock);
    close(serv_sock);
}

void show_error(const char *message) {
    fputs(message, stderr);
    fputc('\n', stderr);
    exit(1);
}
